The use of a strung racket for striking a small, more-or-less resilient object is a common element in many popular games, including tennis, squash, paddle ball, and badminton. The tension in the strings which make up the net of the racket is an important factor in the performance in the racket. In a normal racket, the tension of the strings is set when the strings are placed on the racket and any subsequent adjustment requires considerable time and skill. Because the desired tension varies considerably, depending on the game conditions, a player who is serious about his performance must maintain several rackets. In addition to this problem of the initial tension setting, there is also a tendency for the tension of the strings to change unpredictably with changes in humidity, etc. Both of these problems have been recognized and various solutions proposed to allow on the spot adjustment of a single racket to any desired tension.
An early attempt involved the idea of placing a pneumatically inflatable tube outside the hoop portion of the frame. Because the strings were supported by the external peripheral surface, inflation of the tube would result in a tightening of the strings. The inflation would be carried out using a pump in the handle of the racket. This device was quite complex and, therefore, expensive and was prone to failure of the components. Another concept was to carry the strings which were parallel to the handle, down into the handle and to draw on the strings using a screw and nut arrangement within the handle. Although this structure was quite complex, and considerably more difficult to string than a regular racket, the racket did involve the useful concept that by drawing on the major axis of the eliptical hoop, the minor axis would increase, thus tightening the strings parallel to it. A winch mounted in the handle for drawing the strings could be used to accomplish the same result. In still another construction, the concept of the pneumatic tube on the external periphery of the hoop is carried out using a cable with hooks which capture the outermost ends of the string and draw the strings tight when the cable is drawn toward the handle. All of these structures involve disadvantages which center around the concept that such complex arrangements are expensive to manufacture and difficult to make strong enough to endure the stresses involved in use. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a game racket in which the tension of the strings can be easily adjusted.
Another object of the invention is the provision of a game racket in which the string tightening mechanism is of simple rugged construction.
A further object of the present invention is the provision of a game racket in which the adjusted tension of the strings is uniform over the surface of the net.
It is another object of the instant invention to provide a game racket in which the string tightening device does not detract from the appearance of the racket.
A still further object of the invention is the provision of a game racket having a string tightening adjustment means which does not interfere with the other functional design features of the racket.
It is a further object of the invention to provide a game racket which is both simple and inexpensive to manufacture and which is capable of a long and useful life with a minimum maintenance.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.